178 research outputs found
Comparing Cooling of Warm Mix to Hot Mix Asphalts
Warm mix asphalt (WMA) is increasingly being tried in highway paving in the United States. Apart from environmental benefits, WMA is being considered useful in projects involving long haul distances and late season paving operations due to its material characteristics and the rate of cooling during field compaction. This thesis investigates whether WMA cools at a slower rate than hot mix asphalt (HMA) to offer more compaction time. Following an indirect investigative approach, comparative analysis of field observations with software predicted values for two paving projects was carried out. The results indicated that some types of WMA cool at a slower rate than HMA and would allow a longer period of compaction time to achieve the same density as HMA. The findings presented here can be informative to the asphalt paving industry in considering WMA for use in long haul, nighttime, and late season paving
A clinical study to evaluate the effectiveness of the short proximal femoral nail in the management of unstable intertrochanteric fractures
Background: The objective was to study the effectiveness and drawbacks of short proximal femoral nail in the management of unstable intertrochanteric fractures.Methods: This prospective study was conducted in the department of orthopaedics Al-Ameen medical college, Vijayapura, Karnataka, India from July 2010 to June 2017. Total 175 patients (130 males and 45 females) aged between 41 to 80 years with unstable Intertrochantreric fracture (155 had type IV and 20 had type III according to Boyd and Griffin classification). All patients were operated using Short proximal femoral nail and followed at least for a minimum period of 6 months and were evaluated radiologically and clinically by Kyle’s Criteria.Results: Anatomical reduction was achieved in 125 patients, 105 (60%) had no complications post operatively. Complications included 5 cases of avascular necrosis and screw cut out, 5 cases of delayed union, 5 cases of Z-effect, 20 cases of varus malunion, 10 cases of antirotation screw breakage, 5 cases of distal bolt breakage and 15 cases with lateral thigh discomfort. 125 patients had No shortening and the average shortening was 0.34 cm, average time of union was 19.26 weeks (15-30 weeks) in 170 cases. At the end of 6 months, good to excellent results were seen in 71.5% of cases, 57% patients returned to their pre injury functional level.Conclusions: Short proximal femoral nail provides good fixation for unstable intertrochanteric fractures, if proper pre-operative planning, good reduction and surgical techniques are followed leading to high rate of bone union and minimal soft tissues damage especially for Asian patients with relatively small femora
Deep Reinforcement Learning-Based Mapless Crowd Navigation with Perceived Risk of the Moving Crowd for Mobile Robots
Current state-of-the-art crowd navigation approaches are mainly deep
reinforcement learning (DRL)-based. However, DRL-based methods suffer from the
issues of generalization and scalability. To overcome these challenges, we
propose a method that includes a Collision Probability (CP) in the observation
space to give the robot a sense of the level of danger of the moving crowd to
help the robot navigate safely through crowds with unseen behaviors. We studied
the effects of changing the number of moving obstacles to pay attention during
navigation. During training, we generated local waypoints to increase the
reward density and improve the learning efficiency of the system. Our approach
was developed using deep reinforcement learning (DRL) and trained using the
Gazebo simulator in a non-cooperative crowd environment with obstacles moving
at randomized speeds and directions. We then evaluated our model on four
different crowd-behavior scenarios. The results show that our method achieved a
100% success rate in all test settings. We compared our approach with a current
state-of-the-art DRL-based approach, and our approach has performed
significantly better, especially in terms of social safety. Importantly, our
method can navigate in different crowd behaviors and requires no fine-tuning
after being trained once. We further demonstrated the crowd navigation
capability of our model in real-world tests.Comment: 6 pages, 7 figure
Anemia among women of reproductive age: An overview of global burden, trends, determinants, and drivers of progress in low- and middle-income countries
Relatively little progress has been made in reducing anemia prevalence among women of reproductive age (WRA anemia). Interventions, policies and programs aimed at reducing WRA anemia have the potential to improve overall not only women\u27s, but also children\u27s health and nutrition outcomes. To our knowledge, this is the first review that aimed to compile evidence on the determinants and drivers of WRA anemia reduction in low- and middle-income countries (LMICs). We synthesized the available evidence on the determinants and drivers, including government policies and programs, of WRA anemia and their mitigation strategies across a wide range of countries and geographies, thus contributing to the complex and multifactorial etiology of anemia. We carried out a systematic review of published peer-reviewed and grey literature assessing national or subnational decline in WRA anemia prevalence and the associated drivers in LMICs. Among the 21 studies meeting our inclusion criteria, proximal determinants of healthcare utilization, especially during pregnancy and with the use of contraceptives, were strong drivers of WRA anemia reduction. Changes in other maternal characteristics, such as an increase in age at first pregnancy, BMI, birth spacing, and reduction in parity, were associated with modest improvements in anemia prevalence. Access to fortified foods, especially iron-fortified flour, was also a predictor of a decrease in WRA anemia. Of the intermediate determinants, an increase in household wealth, educational attainment and access to improved sanitation contributed significantly to WRA anemia reduction. Although several common determinants emerged at the proximal and intermediate levels, the set of anemia determinants and the strength of the association between each driver and WRA anemia reduction were unique in each setting included in this review. Further research is needed to provide targeted recommendations for each country and region where WRA anemia prevalence remains high
Public and private control and contestation of public space amid violent conflict in Karachi
"Few cities in South Asia have been affected by violence more than Karachi, Pakistan’s largest city and economic centre. This working paper examines the impacts of the city’s declining security situation on the control and contestation of public space. It focuses specifically on the efforts of public and private actors to protect themselves through the widespread use of physical barriers as a form of conflict infrastructure. To help provide a way forward, recommendations
are presented for planning and managing barriers more effectively and equitably, and for supporting alternative means of security for the poorest and most insecure groups. Particular attention is paid
to the city’s ethnic and religious/sectarian politics and the limited capacity of the authorities, and their difficulties in maintaining neutrality in attempting to intervene.
DSCOT: An NFT-Based Blockchain Architecture for the Authentication of IoT-Enabled Smart Devices in Smart Cities
Smart city architecture brings all the underlying architectures, i.e.,
Internet of Things (IoT), Cyber-Physical Systems (CPSs), Internet of
Cyber-Physical Things (IoCPT), and Internet of Everything (IoE), together to
work as a system under its umbrella. The goal of smart city architecture is to
come up with a solution that may integrate all the real-time response
applications. However, the cyber-physical space poses threats that can
jeopardize the working of a smart city where all the data belonging to people,
systems, and processes will be at risk. Various architectures based on
centralized and distributed mechanisms support smart cities; however, the
security concerns regarding traceability, scalability, security services,
platform assistance, and resource management persist. In this paper, private
blockchain-based architecture Decentralized Smart City of Things (DSCoT) is
proposed. It actively utilizes fog computing for all the users and smart
devices connected to a fog node in a particular management system in a smart
city, i.e., a smart house or hospital, etc. Non-fungible tokens (NFTs) have
been utilized for representation to define smart device attributes. NFTs in the
proposed DSCoT architecture provide devices and user authentication (IoT)
functionality. DSCoT has been designed to provide a smart city solution that
ensures robust security features such as Confidentiality, Integrity,
Availability (CIA), and authorization by defining new attributes and functions
for Owner, User, Fog, and IoT devices authentication. The evaluation of the
proposed functions and components in terms of Gas consumption and time
complexity has shown promising results. Comparatively, the Gas consumption for
minting DSCoT NFT showed approximately 27%, and a DSCoT approve() was
approximately 11% more efficient than the PUF-based NFT solution.Comment: 18 pages, 15 figures, 5 tables, journa
Anticancer efficacy of perillyl alcohol-bearing PLGA microparticles
In the present study, a novel poly-lactic glycolic acid (PLGA)-based microparticle formulation of perillyl alcohol (POH) was prepared and characterized. Further, its efficacy was evaluated against di-methyl benzo anthracene-induced skin papilloma in Swiss albino mice. The characterization studies showed that POH-bearing PLGA microparticles were of the size 768 ± 215 nm with a ζ-potential value of −7.56 ± 0.88 mV. The entrapment efficiency of the active drug in particles was 42.4% ± 3.5%. POH-bearing PLGA microparticles were stable and released entrapped drug gradually over an extended time period. The in vitro efficacy of POH-bearing PLGA microparticles was evaluated by examining their differential cytotoxicity and assessing their ability to inhibit epidermoid carcinoma cell line (A253). The POH-based microparticles when administered to tumor-bearing animals caused greater tumor regression and increased survival rate (∼80%) as compared with the group receiving free form of POH (survival rate 40%). The superiority of POH-PLGA microparticles over free form of POH was further evident from their ability to modulate apoptosis-regulating factors
Quantitatively evaluating the effect of social barriers: a case-control study of family members' opposition and women's intention to use contraception in Pakistan.
BACKGROUND: Uptake of family planning services in Pakistan has remained slow over the past decade despite a rapid increase in availability and awareness, indicating that social barriers may be preventing uptake. Social barriers such as opposition by family members have largely been studied qualitatively; there is a lack of quantitative evidence about the effect of different family members' opposition on women's intention to use contraceptives. The objective of this study was to quantitatively evaluate the effect of family members' opposition to family planning on intention to use contraception amongst poor women in Pakistan who have physical access to family planning services. METHODS: An unmatched case control study (nested within a larger cohort study) was conducted in two public hospitals in Karachi, Pakistan. Univariable and multivariable logistic regression analyses were conducted to compare risk factors between women that were not intending to use any contraceptive methods in the future (cases) and women that were planning to use contraceptive methods (controls). RESULTS: 248 cases and 496 controls were included in the study. Negative contraceptive intent was associated with no knowledge of contraception (AOR = 3.79 [2.43-5.90]; p < 0.001), husband's opposition (AOR = 21.87 [13.21-36.21]; p < 0.001) and mother-in-law's opposition (AOR = 4.06 [1.77-9.30]; p < 0.001). CONCLUSIONS: This study is the first to quantitatively assess the effect of opposition by different family members on women's contraceptive intent in Pakistan. Our results indicate that of all family members, husband's opposition has the strongest effect on women's intention to use contraception, even when the women have knowledge of and physical access to family planning services
Evaluation of the effects of highly saline and warm seawaters on corrosivity of marine assets
In marine environment, the corrosion rate of metallic structures vary remarkably with
the change in climatic conditions and seawater composition across geographical locations. The corrosion in brackish and polluted seawaters is even more complicated due to the presence of different chemical species and untreated effluents. The complex correlation between the above average temperature and salinity with the high nutrient content in polluted seawater tends to accelerate the rate of biological activities and microbiological induced corrosion (MIC). This research paper has investigated the short-term corrosion of cupronickel (Cu-Ni) 90/10 alloy, and mild steel in the highly saline and warm seawaters. Field experiments for general corrosion under fully immersed condition were conducted at two site locations, represented as site 1 for pollutantrich seawaters and site 2 for natural seawaters in the North Indian Ocean. The experiments were conducted for a period of up to two months and coupons for each metal alloy were recovered
from both sites after an exposure period of 15, 30, 45, and 60 days, respectively. In both
environmental conditions, significantly high mass loss and corrosion rates were recorded for each metal alloys. Despite the same temperature of seawater and immersion depth at both sites, average corrosion losses at site 1 were found to be 5 and 3 times higher than that of site 2 for Cu-Ni alloy 90/10, and mild steel coupons, respectively
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